Impact of nano calcium hydroxide and calcium oxide on some metabolic activities and phenolic compounds of Lupinus termis seedlings

Abstract

The effect of 0.5, 1.0 and 2.0 mM nano calcium hydroxide Ca(OH)2 and calcium oxide CaO orbulk calcium carbonate CaCO3 on growth and metabolic changes of Lupines termis seedlings was assessed.Root fresh and dry weights were increased by nano CaO at 0.5 and 1.0 mM compared with the control, whilethey were decreased by increasing nano Ca(OH)2. Shoot fresh and dry weights were increased by increasingthe concentration of nano Ca(OH)2 and CaO reaching their maximum at 0.5 and 2.0 mM, respectively. BulkCaCO3 concentrations increased root and shoot fresh and dry weights at the highest concentration (2mM).The photosynthetic pigments (chl.a, chl.b and carotenoids) were markedly increased with increasing theconcentration of nano Ca (OH)2, nano CaO and bulk CaCO3 with the highest magnitude recorded for nanoCa(OH)2, while the lowest was for CaCO3. The total soluble carbohydrate biosynthesis of both shoot androot was reduced by nano calcium particles, whereas it was enhanced by bulk calcium compared withcontrol. The root soluble protein was decreased by different concentrations of either nano or bulk calcium,while shoot soluble protein was increased by all calcium treatments compared with the control. The nanocalcium especially Ca(OH)2 activated the protein metabolism compared with the bulk. The root and shootphenolic compounds were decreased by different concentrations of either nano or bulk calcium, except of theshoot phenolic compounds at CaCO3. Nano CaO at 0.5 mM increased shoot phenolic compounds by 10%compared with control.